Решите уравнение: (5x-1)(x+2)+3(x-4)(x+4)=2(2x+3)²-8 15 ! ! ❤

5x^2 + 10x - x - 2 + 3(x^2 - 16) = 2(4x^2 + 12x + 9) - 8 
5x^2 + 9x - 2 + 3x^2 - 48 = 8x^2 + 24x + 18 - 8 
8x^2 + 9x - 50 = 8x^2 + 24x + 10
9x - 50 = 24x + 10
9x - 24x = 50 + 10
- 15x = 60
x = - 60/15
x = - 4